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In the present study, two lanthanoid coordination polymers (Ln-CPs) with the chemical formulae of {[Pr(HL)2(H2O)3]·(H2O)4·Cl}n(1) and [Ho(HL)(CH3COO)2(H2O)3]n(2, H2L= 2-(hydroxymethyl)-1H-benzo[d]imidazole-5-carboxylic acid) using Ln3+ions along with asymmetric carboxylic acid ligand H2Lwithin solvothermal circumstance in success. Complexes’ 1–2contractions were discovered via single-crystal X-ray diffraction and shaped in-depth by EA, IR spectroscopy, PXRD along with TGA. Their application values on the sports fasciitis along with corresponding mechanism were studied. Enzyme-linked immunosorbent assay (ELISA) was conducted to measure the content of IL-1β along with IL-18 released into muscle tissue. Then, NF-κb activation in muscle tissue was also determined with real-time reverse transcription-polymerase chain reaction (RT-PCR) assay.

2.25Cr–1Mo–0.25V base metal (BM) and welded metal (WM) with different temper embrittlement states were obtained by isothermal temper embrittlement test. The ductile–brittle transition temperature and the carbide size of temper embrittled 2.25Cr–1Mo–0.25V BM and WM increased with the isothermal tempering time. The increase in temper embrittlement time leads to a decrease in yield strength (YS) and ultimate tensile strength (UTS). Hydrogen embrittlement (HE) can decrease the ductility and increase YS and UTS of the material. The hydrogen embrittlement sensitivity and microstructure analysis both show a combined effect of HE and temper embrittlement. The deeper the temper embrittlement, the more sensitive the material to HE. When the hydrogen content in the material is low, the WM is less susceptible to HE due to its welding defects.

Background:For foamy virus, the transactivator of spumaretrovirus (Tas) could bind directly to target DNA sequences termed as Tas responsive elements and trigger the viral internal promoter (IP) and long terminal repeat (LTR) promoters. The cellular endogenous factors also play an important role in viral gene expressions. We hypothesized that except the viral transcription factor Tas, the cellular endogenous factors also affect the viral gene expression. Methods:The full length of the prototype foamy virus (PFV) genome (U21247) was used to predict the potential binding sites of the transcription factors by online software JASPAR (http://jaspar.genereg.net) and Softberry (http://linux1.softberry.com/berry.phtml?topic=index&group=programs&subgroup=promoter). The Dual-Luciferase® Reporter Assay System (Promega, USA) was used to confirm the relative luciferase activities of the test groups. The different representative activating agents or inhibitors of each canonical signal pathway were used to identify the impact of these pathways on PFV 5′LTR and IP promoters. Results:The results showed different cellular endogenous factors might have respective effects on PFV 5′LTR and IP. It is worth mentioning that activator protein-1 and BCL2-associated athanogene 3, 2 kinds of vital proteins associated with NF-κB and PKC pathways, could activate the basal activity of 5′LTR and IP promoters but inhibit the Tas-regulated activity of both promoters. Furthermore, PFV Tas was identified to trigger the transcription of the NF-κB promoter. Conclusion:NF-κB had a negative effect on PFV 5′LTR and IP promoter activities, the PKC pathway might upregulate 5′LTR and IP promoter activities, and the JNK and NF-AT signal pathway could increase the Tas-regulated promoter activity of PFV 5′LTR. This study sheds light on the interaction between PFV and the host cell and may help utilize the viral promoters in retroviral vectors designed for gene transfer experiments.

This study was devoted to an investigation of the effects of the average temperature and dwell on the thermal-mechanical fatigue (TMF) behaviour of P92 steel at elevated temperatures in the range of 350–650°C. The results revealed that increased average temperature decreased the in-phase TMF (IPTMF), out-of-phase TMF (OPTMF), and isothermal fatigue (IF) life values, and its effect was more significant in the range of 400–450°C. The effect of a short dwell time on the IPTMF life was dependent on the form of dwell, because tensile dwell decreased the IPTMF life and symmetric dwell increased the IPTMF life. Both creep stress relaxation (CSR) and dynamic strain ageing (DSA) were detected under IPTMF cycling. The application of dwell enhanced the CSR phenomenon. In contrast, the DSA effect was restrained, which was beneficial for fatigue resistance. The appearance of crack tip blunting and crack branching because of symmetric dwell indicated the retardation of crack propagation under the combined effects of enhanced CSR and the disappearance of the DSA phenomenon. In all cases, the transformation of lath structures into substructures was the dominant deformation mechanism. In addition, the equiaxial subgrain grew with increases in the strain amplitude and dwell time. Finally, the application of the current life models to P92 steel fatigue life prediction under both IF and TMF cycling were evaluated. Because of the insufficiency of the current models, a modified Coffin–Manson model is proposed by incorporating the mean stress and temperature into power law forms.

The stress field, constraint effect, and fracture mode transition at crack tip of mixed mode I-II-III inclination surface crack under compression have been investigated. The effects of geometrical configurations (relative crack depth and aspect ratio), friction coefficient, and biaxial scale factor on stress intensity factor (KII and KIII) and in-plane constraint parameter T-stress are quantitatively studied, the stress field at different crack inclination angles under tension and compression are compared, the failure mode at special locations along crack front of inclination surface crack is analyzed according to the generalized maximum tangential stress criterion (GMTS). The relative crack depth has slight effect on stress intensity factor and T-stress, and aspect ratio has a significant effect on stress intensity factor and T-stress. The friction coefficient decreases the magnitude of stress intensity factor and increases the magnitude of T-stress, the greater the crack inclination angle is, the more pronounced the effect is when crack inclination angle greater than 30 deg. The stress distribution around crack tip under tension and compression is completely different. At free surface, the crack will failure in-plane shear mode II sliding crack, and at the deepest part of crack, the crack will start as out-plane shear mode III tearing crack under compression.

At present the orthotropic pressurized metal structure is generally used as the isotropic one, ignoring the anisotropic characteristics of material caused during rolling process. At the same time, the elastic stress analysis design method is commonly used in pressure vessel, and the load capacity coming from plasticity of material has not been utilized. Therefore, elastic-plastic analysis of orthotropic pressurized structure is of great theoretical significance and engineering value. In present paper the limit load of orthotropic titanium cylindrical shell under internal pressure was studied. By finite element method with twice elastic slope criterion the variations of limit load for orthotropic and isotropic titanium cylindrical shells under different diameter-thickness ratios were investigated. The effect of orthotropic mechanical property on limit load of titanium cylindrical shell was discussed. At the same time, the difference of limit loads between orthotropic and isotropic titanium cylindrical shells was compared. The calculation results show that the limit loads of orthotropic and isotropic titanium cylindrical shell increase with the diameter-thickness ratio, and the limit load of orthotropic titanium cylindrical shell increases more obviously. Additionally, if the yield strength of isotropic cylindrical shell is the same as or close to the yield strength of circumferential direction for orthotropic titanium cylindrical shell, the difference of limit load is smaller. While the yield strength of isotropic cylindrical shell is much different from the yield strength of circumferential direction for orthotropic titanium cylindrical shell, the difference of the limit load is higher.

The anisotropic tensile mechanical properties of pure titanium (TA2) tubes were studied by means of theoretical analysis, finite element simulation and tensile tests. Based on the stress analysis of circumferential tensile of TA2 tube, an equation for calculating the tangential force of circumferential tensile specimen was established, and the relationship among tangential force, friction and position of ring specimen was analyzed. The finite element simulation analysis of circumferential tensile process of TA2 ring specimen was carried out, which verified the tangential force equation derived from theoretical analysis. The effect of gauge length and friction on necking and tensile load was analyzed, and the optimal gauge length was selected for the ring hoop tensile test. Finally, the axial and circumferential tensile digital image correlation experiments were carried out to verify the theoretical and finite element simulation results. The friction coefficient between TA2 tube and D-blocks (using Teflon lubricant) was determined by the inverse finite element method and the friction experiment, and the true stress–strain curve of TA2 tube was obtained. The results show that the axial and circumferential mechanical behaviors of TA2 tubes are significantly different and anisotropic.

The structure of cylindrical shell with nozzle has been widely used in pressure equipment. The analysis and design for the structure of cylindrical shell with nozzle are generally based on the isotropy of metal at present, which may cause certain error and risk. Because of the approaches of rolling, heat treatment, and so on, the materials’ properties are different along each direction in practical engineering. In this paper, based on anisotropic thin shell theory, the analysis for orthotropic pressurized structure of thin-walled cylindrical shell with nozzle was conducted by using finite element software Ansys. The influences of thickness ratio and elastic modulus ratio were comprehensively considered, and also compared with the stress results under isotropic structure. The analysis results show that the values of stress and stress concentration factor for the structure of cylindrical shell with nozzle decrease with elastic modulus ratio, but increase with thickness ratio. Compared with the influence of thickness ratio, the elastic modulus ratio has significant effect on stress level. The rational use of the material anisotropic property can optimize the structure of thin-walled cylindrical shell with nozzle. The results in present paper provided a reference for the design of orthotropic pressurized structure of cylindrical shell with nozzle.

Strain-based failure assessment methods have been usually used in recent years to propose the fitness-for-service flaws. In this paper, the stress-based and strain-based failure assessment diagram (SB-FAD) approaches were reviewed firstly. Then, SB-FAD approach was used to the material commercially pure titanium TA2 with high strain-hardening coefficient. Several failure assessment curves obtained from strain-based method for four typical specimens, i.e., CCP (center-cracked plate), DECP (double edge cracked plate), SECP (single edge cracked plate) and CT (compact tension) were proposed. It was found that the geometries and crack sizes had obvious effects on the failure assessment curves. By comparing with the stress-based failure assessment curves, the traditional strain-based failure assessment curves could lead to more conservatism in the stage after yielding. However, the SB-FAD modified by Ainsworth can be used.

Transient receptor potential vanilloid 1 (TRPV1) channel has been found to be expressed in a variety of tissues over the last few years, including the central nervous system (CNS). However, the distribution of TRPV1 in the CNS remains a controversial question. Here, we reveal that the expression of TRPV1 can be detected in the C57BL6 mouse hippocampus and cortex using real-time PCR and western blot. Beyond that, mRNA and protein expression levels of TRPV1 show dynamic changes during brain development. Compared with the earliest timepoint examined at 2 weeks, the expression levels of mRNA progressively increased at 4 and 8 weeks, peaking at the later timepoint, then declined at 16 weeks but remained elevated. However, compared with 2-week-old mice, the expression levels of the other three groups (4-, 8-, and 16-week-old mice) increased overall. These results indicate that TRPV1 channel expression is detectable in the CNS and it varies during postnatal development.

This paper investigates a kind of Chinese Traditional Medicine (TCM) pulse state diagnosis sensor which is based on sound detection. This method has many advantages and is in line with the TCM pulse state multi-attribute characteristics. First the sound measurement method was designed. Then the verification experiment of electret microphone was studied. The experiment results shown some electret microphones are available for low frequency and low energy vibration signal which is similar to TCM pulse state signal measurement. Eventually it comes to the conclusion that this pulse acquisition mode is available method and can effectively reveal the different kinds of pulse signal characteristic differences. Boys and girls TCM pulse state signal were detected separately. It shows that Different gender has different pulse state and the pulse shape is also different.

The creep of materials makes it difficulty to determine the limit load of component at high temperature. In this paper, limit load was obtained by finite element simulation according to isochronous stress versus cumulative strain data and creep failure criterion at high temperature. Firstly, isochronous stress versus cumulative strain data of P91 steel was generated. In finite element analysis code ABAQUS, isochronous stress versus cumulative strain data was replaced by equivalent elastic-plastic constitutive relation. Then, sustained load versus cumulative strain curves at high temperature during service was obtained after finite element simulation. At last, limit load at high temperature during given working hours was determined based on the restriction of total strain at key point of specific component. The restriction of total strain which could also be regarded as long-term fracture strain was discussed in this paper. Finite element simulation of limit load of component at high temperature is simple and reasonable. Limit load of complex component at high temperature during given working hours can be obtained by this method. Using this method, limit loads of a pipe with local wall thinning defect and a branch junction at high temperature during given working hours were obtained as examples.

In engineering, many pressure pipes are made of steels with good plasticity, which are subject to internal pressure, axial force, shear force, bending moment, torsion moment or their combined loads. The plastic limit load is an important indicator of the load capacity of pressure pipe. According to Hill yield function, the theoretical solutions of limit load of orthotropic cylindrical pipe under various combined loads under internal pressure, axial force, shear force, torsion moment, and bending moment have been derived on the basis of elastic perfectly plastic constitutive model. The effects of radial stress on different combined limit loads of cylindrical pipe are explored and these results show that the radial stress should be considered about the limit load calculation especially for thick-walled cylindrical pipe. The interactions of various load combination are analyzed in detail and drawn with the interaction curves. For isotropic cylindrical pipe, the limit load increases with the yield strength. For the orthotropic cylindrical pipe, the limit loads of cylindrical pipe under axial force, bending moment, shear force, and torsion moment without internal pressure are only related to the axial yield strength. The limit bending moment is mainly dependent on the axial yield strength when internal pressure is lower, while the impact of the circumferential yield strength of orthotropic cylindrical pipe is obvious when internal pressure is some higher. When the axial yield strength of orthotropic cylindrical pipe is the same, the circumferential yield strength can enhance the limit axial load, limit torsion moment, and limit shear load. Under the different load conditions including internal pressure, bending moment, axial force, shear force, and torsion moment or their combined loads, the relation of limit bending moment with yield strength ratio is diverse, which is decide by the load combination, the circumferential yield strength, and the axial yield strength.